The UMC has some info. I do not have it on my laptop. But here is some good info I found online.
I do know that there are cfm requirements for LF of hood. And that the kitchen area is required to be negative pressure.
Hope this gets you started in thr right direction.
I have also done duct work for these hoods and they are well made.
http://www.captiveaire.com/catalogco...ds/ndi/ndi.asp
The hardest part of doing hoods in my opinion is wrapping the duct with fire wrap.......it's a frickin night mare.